Need help with E6420, please!

[Oihan]

Hello, I'm new to overlocking. I've read the guidlines associated with OC'ing a dual core CPU and I understand that the Vcore will have to be raised if one plans to use a much higher FSB speed; that the NB voltage might have to be increased; that the RAM timings should be "loose" at first...voltage might be adjusted as well; and something about adjusting the FSB VTT a tad if need be. ...Something along those lines anyway. But how does one know which one needs to be adjusted when and by how much?

I have a E6420 with a 'stock' voltage (according to the BIOS on my MSI P6N SLI Platinum mobo) of 1.28v; 2 GB of DDR2 800 (4-4-4-12; 2.2v - rated) Patriot Memory RAM. I'm also using the stock HSF. Now, without even adjusting the Vcore, I can get the FSB to 375 with the CPU at 3 GHz. I didn't do any of the prime95-like tests but it seemed stable enough to play my games and surf the web. However, when I try to get to 3.2 GHz with a 1:1 ratio...the computer won't even POST and it gives me a blank screen. I've tried increasing the Vcore a little and then to 1.35v (tis what was rated as the max on the box)...no go. So I figure it's either the RAM timings, NB voltage, or the FSB VTT...or a combination of both that I need to adjust. I’m just at a loss for which one to tweak (first).

I’ve tried reading the manual that came with the board…but it wasn’t so useful. “>FSB VTT Voltage : This item allows you to set the FSB VTT voltage.” Well geez, thanks for stating the obvious, now I know what it does. -_-

I’ve already disabled all the features in BIOS that would hinder overclocking (like SpeedStep) and I’ve tried adjusting the voltages here and there by a tad and adjusted the ram timings to 5-5-5-15…but I can’t say that I really know what I’m doing.

So…if anyone could please help me I’d greatly appreciate it. Thanks!

Oihan

 

[BillParrish]

You dont need to worry about the FSB Vtt voltage at the moment. Its for extream overclocking and it causes more problems than it probally fixes.

Put your Vcore to 1.350 memory voltage to the high end of what the manuf recommends memory timings like you have at 5 5 5 15 memory speed on auto.

now start raising the FSB in 10 or 20MHz increments and see where your cpu will go.

I like to make a memtest86+ boot cd and put CD first in the boot order. Let the machine boot into memtest and run just the very first single test, then if no errors, reboot, raise FSB, rinse and repeat, no chance of corrupting your windows install doing that.

See where that gets you and post back.

 

[Oihan]

You dont need to worry about the FSB Vtt voltage at the moment. Its for extream overclocking and it causes more problems than it probally fixes.

Put your Vcore to 1.350 memory voltage to the high end of what the manuf recommends memory timings like you have at 5 5 5 15 memory speed on auto.

now start raising the FSB in 10 or 20MHz increments and see where your cpu will go.

I like to make a memtest86+ boot cd and put CD first in the boot order. Let the machine boot into memtest and run just the very first single test, then if no errors, reboot, raise FSB, rinse and repeat, no chance of corrupting your windows install doing that.

See where that gets you and post back.

Hey, thanks for the response!

I did what you suggested. I set the Vcore to 1.36v (because it'd vdroop to 1.352 in the BIOS and I wanted to make sure it was at least at 1.35v) and I had the memory voltage set at 2.2v. The highest I could get the FSB to was 375.5MHz (1502MHz) with the DRAM at 375.5MHz (751MHz). With the FSB at 375.75MHz (1503MHz) Memtest86+ wouldn't/couldn't start its test(s). Memory timings were at 5-5-5-15.

There was three options when I was upping the FSB (Auto, Linked, and Manual) and I used 'Linked.' I'm assuming 'Linked' automatically sets the DRAM speed while I manually increase the FSB for it was only giving me the option to manually adjust the FSB. So I hope I was doing things right as you suggested. Sorry if I'm misusing any of the terms.

I really hope that the CPU I have isn't somehow gimped/'broke'/whatever-the-appropriate-term-would-be...cause I can get the CPU to 3GHz w/o having to up the Vcore...and upping it by .0875 and not being able to get the CPU any faster blows chunks.

Shall I try upping the Vcore some more? Thanks again!

 

[Oihan]

I'm still having trouble getting past the 3GHz barrier (would like 1:1 with my RAM at 400MHz). However, I'm seeing in some other threads that if I wanted my CPU at 3.2GHz that I'd want the Mem Frequency set at 266.5MHz (533MHz) for the 1:1? Would anyone else have any ideas? Thanks again.